docs: def _get_authorization_headers(self) -> dict:
          """Constructs and returns the Authorization header for the client app.
  
          Args:
              None
  
          Returns:
              header dict for communicating with the authorization endpoints
          """
          auth = base64.encodestring((self.client_id + ':' + self.client_secret).encode('latin-1')).decode('latin-1')
          auth = auth.replace('\n', '').replace(' ', '')
          auth = 'Basic {}'.format(auth)
          headers = {'Authorization': auth}
          return headers